/**
 * (c) Meta Platforms, Inc. and affiliates. Confidential and proprietary.
 *
 * This code essentially is taken from
 * https://github.com/satazor/SparkMD5/blob/master/spark-md5.js.
 * The code has progressive hashing and support for typed buffers.
 * The code is distributed under the most unrestrictive license ever
 * https://github.com/satazor/SparkMD5/blob/master/LICENSE.
 *
 * @format
 * @noflow
 * @oncall i18n_fbt_oss
 */

'use strict';

/**
 * Fastest md5 implementation around (JKM md5)
 * Credits: Joseph Myers
 *
 * @see http://www.myersdaily.org/joseph/javascript/md5-text.html
 * @see http://jsperf.com/md5-shootout/7
 */

/* this function is much faster,
   so if possible we use it. Some IEs
   are the only ones I know of that
   need the idiotic second function,
   generated by an if clause.  */
let add32 = function (a, b) {
    return (a + b) & 0xffffffff;
  },
  cmn = function (q, a, b, x, s, t) {
    a = add32(add32(a, q), add32(x, t));
    return add32((a << s) | (a >>> (32 - s)), b);
  },
  ff = function (a, b, c, d, x, s, t) {
    return cmn((b & c) | (~b & d), a, b, x, s, t);
  },
  gg = function (a, b, c, d, x, s, t) {
    return cmn((b & d) | (c & ~d), a, b, x, s, t);
  },
  hh = function (a, b, c, d, x, s, t) {
    return cmn(b ^ c ^ d, a, b, x, s, t);
  },
  ii = function (a, b, c, d, x, s, t) {
    return cmn(c ^ (b | ~d), a, b, x, s, t);
  },
  md5cycle = function (x, k) {
    let a = x[0],
      b = x[1],
      c = x[2],
      d = x[3];

    a = ff(a, b, c, d, k[0], 7, -680876936);
    d = ff(d, a, b, c, k[1], 12, -389564586);
    c = ff(c, d, a, b, k[2], 17, 606105819);
    b = ff(b, c, d, a, k[3], 22, -1044525330);
    a = ff(a, b, c, d, k[4], 7, -176418897);
    d = ff(d, a, b, c, k[5], 12, 1200080426);
    c = ff(c, d, a, b, k[6], 17, -1473231341);
    b = ff(b, c, d, a, k[7], 22, -45705983);
    a = ff(a, b, c, d, k[8], 7, 1770035416);
    d = ff(d, a, b, c, k[9], 12, -1958414417);
    c = ff(c, d, a, b, k[10], 17, -42063);
    b = ff(b, c, d, a, k[11], 22, -1990404162);
    a = ff(a, b, c, d, k[12], 7, 1804603682);
    d = ff(d, a, b, c, k[13], 12, -40341101);
    c = ff(c, d, a, b, k[14], 17, -1502002290);
    b = ff(b, c, d, a, k[15], 22, 1236535329);

    a = gg(a, b, c, d, k[1], 5, -165796510);
    d = gg(d, a, b, c, k[6], 9, -1069501632);
    c = gg(c, d, a, b, k[11], 14, 643717713);
    b = gg(b, c, d, a, k[0], 20, -373897302);
    a = gg(a, b, c, d, k[5], 5, -701558691);
    d = gg(d, a, b, c, k[10], 9, 38016083);
    c = gg(c, d, a, b, k[15], 14, -660478335);
    b = gg(b, c, d, a, k[4], 20, -405537848);
    a = gg(a, b, c, d, k[9], 5, 568446438);
    d = gg(d, a, b, c, k[14], 9, -1019803690);
    c = gg(c, d, a, b, k[3], 14, -187363961);
    b = gg(b, c, d, a, k[8], 20, 1163531501);
    a = gg(a, b, c, d, k[13], 5, -1444681467);
    d = gg(d, a, b, c, k[2], 9, -51403784);
    c = gg(c, d, a, b, k[7], 14, 1735328473);
    b = gg(b, c, d, a, k[12], 20, -1926607734);

    a = hh(a, b, c, d, k[5], 4, -378558);
    d = hh(d, a, b, c, k[8], 11, -2022574463);
    c = hh(c, d, a, b, k[11], 16, 1839030562);
    b = hh(b, c, d, a, k[14], 23, -35309556);
    a = hh(a, b, c, d, k[1], 4, -1530992060);
    d = hh(d, a, b, c, k[4], 11, 1272893353);
    c = hh(c, d, a, b, k[7], 16, -155497632);
    b = hh(b, c, d, a, k[10], 23, -1094730640);
    a = hh(a, b, c, d, k[13], 4, 681279174);
    d = hh(d, a, b, c, k[0], 11, -358537222);
    c = hh(c, d, a, b, k[3], 16, -722521979);
    b = hh(b, c, d, a, k[6], 23, 76029189);
    a = hh(a, b, c, d, k[9], 4, -640364487);
    d = hh(d, a, b, c, k[12], 11, -421815835);
    c = hh(c, d, a, b, k[15], 16, 530742520);
    b = hh(b, c, d, a, k[2], 23, -995338651);

    a = ii(a, b, c, d, k[0], 6, -198630844);
    d = ii(d, a, b, c, k[7], 10, 1126891415);
    c = ii(c, d, a, b, k[14], 15, -1416354905);
    b = ii(b, c, d, a, k[5], 21, -57434055);
    a = ii(a, b, c, d, k[12], 6, 1700485571);
    d = ii(d, a, b, c, k[3], 10, -1894986606);
    c = ii(c, d, a, b, k[10], 15, -1051523);
    b = ii(b, c, d, a, k[1], 21, -2054922799);
    a = ii(a, b, c, d, k[8], 6, 1873313359);
    d = ii(d, a, b, c, k[15], 10, -30611744);
    c = ii(c, d, a, b, k[6], 15, -1560198380);
    b = ii(b, c, d, a, k[13], 21, 1309151649);
    a = ii(a, b, c, d, k[4], 6, -145523070);
    d = ii(d, a, b, c, k[11], 10, -1120210379);
    c = ii(c, d, a, b, k[2], 15, 718787259);
    b = ii(b, c, d, a, k[9], 21, -343485551);

    x[0] = add32(a, x[0]);
    x[1] = add32(b, x[1]);
    x[2] = add32(c, x[2]);
    x[3] = add32(d, x[3]);
  },
  /* there needs to be support for Unicode here,
   * unless we pretend that we can redefine the MD-5
   * algorithm for multi-byte characters (perhaps
   * by adding every four 16-bit characters and
   * shortening the sum to 32 bits). Otherwise
   * I suggest performing MD-5 as if every character
   * was two bytes--e.g., 0040 0025 = @%--but then
   * how will an ordinary MD-5 sum be matched?
   * There is no way to standardize text to something
   * like UTF-8 before transformation; speed cost is
   * utterly prohibitive. The JavaScript standard
   * itself needs to look at this: it should start
   * providing access to strings as preformed UTF-8
   * 8-bit unsigned value arrays.
   */
  md5blk = function (s) {
    let md5blks = [],
      i; /* Andy King said do it this way. */

    for (i = 0; i < 64; i += 4) {
      md5blks[i >> 2] =
        s.charCodeAt(i) +
        (s.charCodeAt(i + 1) << 8) +
        (s.charCodeAt(i + 2) << 16) +
        (s.charCodeAt(i + 3) << 24);
    }
    return md5blks;
  },
  md5blk_array = function (a) {
    let md5blks = [],
      i; /* Andy King said do it this way. */

    for (i = 0; i < 64; i += 4) {
      md5blks[i >> 2] =
        a[i] + (a[i + 1] << 8) + (a[i + 2] << 16) + (a[i + 3] << 24);
    }
    return md5blks;
  },
  md51 = function (s) {
    var n = s.length,
      state = [1732584193, -271733879, -1732584194, 271733878],
      i,
      length,
      tail,
      tmp,
      lo,
      hi;

    for (i = 64; i <= n; i += 64) {
      md5cycle(state, md5blk(s.substring(i - 64, i)));
    }
    s = s.substring(i - 64);
    length = s.length;
    tail = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
    for (i = 0; i < length; i += 1) {
      tail[i >> 2] |= s.charCodeAt(i) << (i % 4 << 3);
    }
    tail[i >> 2] |= 0x80 << (i % 4 << 3);
    if (i > 55) {
      md5cycle(state, tail);
      for (i = 0; i < 16; i += 1) {
        tail[i] = 0;
      }
    }

    // Beware that the final length might not
    // fit in 32 bits so we take care of that
    tmp = n * 8;
    tmp = tmp.toString(16).match(/(.*?)(.{0,8})$/);
    lo = parseInt(tmp[2], 16);
    hi = parseInt(tmp[1], 16) || 0;

    tail[14] = lo;
    tail[15] = hi;

    md5cycle(state, tail);
    return state;
  },
  md51_array = function (a) {
    var n = a.length,
      state = [1732584193, -271733879, -1732584194, 271733878],
      i,
      length,
      tail,
      tmp,
      lo,
      hi;

    for (i = 64; i <= n; i += 64) {
      md5cycle(state, md5blk_array(a.subarray(i - 64, i)));
    }

    // Not sure if it is a bug, however IE10 will
    // always produce a sub array of length 1
    // containing the last element of the parent
    // array if the sub array specified starts
    // beyond the length of the parent array - weird.
    // https://connect.microsoft.com/IE
    // /feedback/details/771452/typed-array-subarray-issue
    a = i - 64 < n ? a.subarray(i - 64) : new Uint8Array(0);

    length = a.length;
    tail = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
    for (i = 0; i < length; i += 1) {
      tail[i >> 2] |= a[i] << (i % 4 << 3);
    }

    tail[i >> 2] |= 0x80 << (i % 4 << 3);
    if (i > 55) {
      md5cycle(state, tail);
      for (i = 0; i < 16; i += 1) {
        tail[i] = 0;
      }
    }

    // Beware that the final length might not fit
    // in 32 bits so we take care of that
    tmp = n * 8;
    tmp = tmp.toString(16).match(/(.*?)(.{0,8})$/);
    lo = parseInt(tmp[2], 16);
    hi = parseInt(tmp[1], 16) || 0;

    tail[14] = lo;
    tail[15] = hi;

    md5cycle(state, tail);

    return state;
  },
  hex_chr = [
    '0',
    '1',
    '2',
    '3',
    '4',
    '5',
    '6',
    '7',
    '8',
    '9',
    'a',
    'b',
    'c',
    'd',
    'e',
    'f',
  ],
  rhex = function (n) {
    let s = '',
      j;
    for (j = 0; j < 4; j += 1) {
      s += hex_chr[(n >> (j * 8 + 4)) & 0x0f] + hex_chr[(n >> (j * 8)) & 0x0f];
    }
    return s;
  },
  hex = function (x) {
    let i;
    for (i = 0; i < x.length; i += 1) {
      x[i] = rhex(x[i]);
    }
    return x.join('');
  },
  md5 = function (s) {
    return hex(md51(s));
  },
  /**
   * SparkMD5 OOP implementation.
   *
   * Use this class to perform an incremental md5, otherwise use the
   * static methods instead.
   */
  SparkMD5 = function () {
    // call reset to init the instance
    this.reset();
  };

// In some cases the fast add32 function cannot be used..
if (md5('hello') !== '5d41402abc4b2a76b9719d911017c592') {
  add32 = function (x, y) {
    const lsw = (x & 0xffff) + (y & 0xffff),
      msw = (x >> 16) + (y >> 16) + (lsw >> 16);
    return (msw << 16) | (lsw & 0xffff);
  };
}

/**
 * Appends a string.
 * A conversion will be applied if an utf8 string is detected.
 *
 * @param {String} str The string to be appended
 *
 * @return {SparkMD5} The instance itself
 */
SparkMD5.prototype.append = function (str) {
  // converts the string to utf8 bytes if necessary
  if (/[\u0080-\uFFFF]/.test(str)) {
    str = unescape(encodeURIComponent(str));
  }

  // then append as binary
  this.appendBinary(str);

  return this;
};

/**
 * Appends a binary string.
 *
 * @param {String} contents The binary string to be appended
 *
 * @return {SparkMD5} The instance itself
 */
SparkMD5.prototype.appendBinary = function (contents) {
  this._buff += contents;
  this._length += contents.length;

  var length = this._buff.length,
    i;

  for (i = 64; i <= length; i += 64) {
    md5cycle(this._state, md5blk(this._buff.substring(i - 64, i)));
  }

  this._buff = this._buff.substr(i - 64);

  return this;
};

/**
 * Finishes the incremental computation, reseting the internal state and
 * returning the result.
 * Use the raw parameter to obtain the raw result instead of the hex one.
 *
 * @param {Boolean} raw True to get the raw result, false to get the hex result
 *
 * @return {String|Array} The result
 */
SparkMD5.prototype.end = function (raw) {
  let buff = this._buff,
    length = buff.length,
    i,
    tail = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
    ret;

  for (i = 0; i < length; i += 1) {
    tail[i >> 2] |= buff.charCodeAt(i) << (i % 4 << 3);
  }

  this._finish(tail, length);
  ret = !!raw ? this._state : hex(this._state);

  this.reset();

  return ret;
};

/**
 * Finish the final calculation based on the tail.
 *
 * @param {Array}  tail   The tail (will be modified)
 * @param {Number} length The length of the remaining buffer
 */
SparkMD5.prototype._finish = function (tail, length) {
  let i = length,
    tmp,
    lo,
    hi;

  tail[i >> 2] |= 0x80 << (i % 4 << 3);
  if (i > 55) {
    md5cycle(this._state, tail);
    for (i = 0; i < 16; i += 1) {
      tail[i] = 0;
    }
  }

  // Do the final computation based on the tail and length
  // Beware that the final length may not fit in 32 bits so we take care of that
  tmp = this._length * 8;
  tmp = tmp.toString(16).match(/(.*?)(.{0,8})$/);
  lo = parseInt(tmp[2], 16);
  hi = parseInt(tmp[1], 16) || 0;

  tail[14] = lo;
  tail[15] = hi;
  md5cycle(this._state, tail);
};

/**
 * Resets the internal state of the computation.
 *
 * @return {SparkMD5} The instance itself
 */
SparkMD5.prototype.reset = function () {
  this._buff = '';
  this._length = 0;
  this._state = [1732584193, -271733879, -1732584194, 271733878];

  return this;
};

/**
 * Releases memory used by the incremental buffer and other additional
 * resources. If you plan to use the instance again, use reset instead.
 */
SparkMD5.prototype.destroy = function () {
  delete this._state;
  delete this._buff;
  delete this._length;
};

/**
 * Performs the md5 hash on a string.
 * A conversion will be applied if utf8 string is detected.
 *
 * @param {String}  str The string
 * @param {Boolean} raw True to get the raw result, false to get the hex result
 *
 * @return {String|Array} The result
 */
SparkMD5.hash = function (str, raw) {
  // converts the string to utf8 bytes if necessary
  if (/[\u0080-\uFFFF]/.test(str)) {
    str = unescape(encodeURIComponent(str));
  }

  const hash = md51(str);

  return !!raw ? hash : hex(hash);
};

/**
 * Performs the md5 hash on a binary string.
 *
 * @param {String}  content The binary string
 * @param {Boolean} raw True to get the raw result, false to get the hex result
 *
 * @return {String|Array} The result
 */
SparkMD5.hashBinary = function (content, raw) {
  const hash = md51(content);

  return !!raw ? hash : hex(hash);
};

/**
 * SparkMD5 OOP implementation for array buffers.
 *
 * Use this class to perform an incremental md5 ONLY for array buffers.
 */
SparkMD5.ArrayBuffer = function () {
  // call reset to init the instance
  this.reset();
};

/**
 * Appends an array buffer.
 *
 * @param {ArrayBuffer} arr The array to be appended
 *
 * @return {SparkMD5.ArrayBuffer} The instance itself
 */
SparkMD5.ArrayBuffer.prototype.append = function (arr) {
  // TODO: we could avoid the concatenation here
  // but the algorithm would be more complex
  // if you find yourself needing extra performance, please make a PR.
  let buff = this._concatArrayBuffer(this._buff, arr),
    length = buff.length,
    i;

  this._length += arr.byteLength;

  for (i = 64; i <= length; i += 64) {
    md5cycle(this._state, md5blk_array(buff.subarray(i - 64, i)));
  }

  // Avoids IE10 weirdness (documented above)
  this._buff = i - 64 < length ? buff.subarray(i - 64) : new Uint8Array(0);

  return this;
};

/**
 * Finishes the incremental computation, reseting the internal state and
 * returning the result.
 * Use the raw parameter to obtain the raw result instead of the hex one.
 *
 * @param {Boolean} raw True to get the raw result, false to get the hex result
 *
 * @return {String|Array} The result
 */
SparkMD5.ArrayBuffer.prototype.end = function (raw) {
  let buff = this._buff,
    length = buff.length,
    tail = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
    i,
    ret;

  for (i = 0; i < length; i += 1) {
    tail[i >> 2] |= buff[i] << (i % 4 << 3);
  }

  this._finish(tail, length);
  ret = !!raw ? this._state : hex(this._state);

  this.reset();

  return ret;
};

SparkMD5.ArrayBuffer.prototype._finish = SparkMD5.prototype._finish;

/**
 * Resets the internal state of the computation.
 *
 * @return {SparkMD5.ArrayBuffer} The instance itself
 */
SparkMD5.ArrayBuffer.prototype.reset = function () {
  this._buff = new Uint8Array(0);
  this._length = 0;
  this._state = [1732584193, -271733879, -1732584194, 271733878];

  return this;
};

/**
 * Releases memory used by the incremental buffer and other additional
 * resources. If you plan to use the instance again, use reset instead.
 */
SparkMD5.ArrayBuffer.prototype.destroy = SparkMD5.prototype.destroy;

/**
 * Concats two array buffers, returning a new one.
 *
 * @param  {ArrayBuffer} first  The first array buffer
 * @param  {ArrayBuffer} second The second array buffer
 *
 * @return {ArrayBuffer} The new array buffer
 */
SparkMD5.ArrayBuffer.prototype._concatArrayBuffer = function (first, second) {
  const firstLength = first.length,
    result = new Uint8Array(firstLength + second.byteLength);

  result.set(first);
  result.set(new Uint8Array(second), firstLength);

  return result;
};

/**
 * Performs the md5 hash on an array buffer.
 *
 * @param {ArrayBuffer} arr The array buffer
 * @param {Boolean} raw True to get the raw result, false to get the hex result
 *
 * @return {String|Array} The result
 */
SparkMD5.ArrayBuffer.hash = function (arr, raw) {
  const hash = md51_array(new Uint8Array(arr));
  return !!raw ? hash : hex(hash);
};

module.exports = SparkMD5;
